In environments like working environments or private environments it is desired in some situations to prevent that a communication reaches a third listener. A communication can be a confidential conversation of two persons or of a person having a phone call. The third listener can be a third person, e.g. an eavesdropper, or a device able to record or transmit the communication. In some environments it may be desired to prevent an acoustic signal to reach a person. The acoustic signal could be a noise of a machine or a sound emission of a loudspeaker. The person might desire a certain degree of quietness instead of hearing the acoustic signal.
There are concepts for attenuating an acoustic signal. A concept for attenuating an acoustic signal can be called noise cancelling. By using a noise cancelling method, the acoustic signal may be cancelled at least to a certain degree such that a loudness or sound level of the acoustic signal may be attenuated at least at a predefined position.
Noise cancelling devices may be configured to attenuate an acoustic signal by superimposing a countersignal with the acoustic signal. Devices like noise cancelling headphones may attenuate an acoustic signal arriving at a user wearing the noise cancelling headphones such that the user does not hear the acoustic signal anymore. For example, a sound level of the acoustic signal perceived by the user wearing the noise cancelling headphones is lower than a sound level perceived by the user without the noise cancelling headphones. Here, the predefined position may be a user's ear. In another example, a suppression speaker may be provided in a mobile phone, the suppression speaker outputting a countersignal of a speaking signal of a user of the mobile device. Due to superimposing the countersignal with the speaking signal, the speaking signal may be attenuated within a suppression zone. Here, the predefined position may be a position within the suppression zone.
Concepts for attenuating an acoustic signal may show a lack of comfort as a user wearing noise cancelling headphones on her head may feel uncomfortable. Concepts for attenuating an acoustic signal may be ineffective as an acoustic signal of a conversation may reach to a third listener despite a suppression speaker, e.g. if the third listener is not located within the suppression zone. There may be a demand for improved concepts for noise cancelling.